TThe Tim Ferriss Show
← All frameworks
StrategyJohn List

Theory-of-Mind Primitives

Model another person's preferences, beliefs, and constraints before acting

Difficulty
Moderate
Time to result
~weeks to results
Steps
5
Confidence
99%

Theory of mind is the ability to put yourself in another person's position and use that model to choose your own action. List operationalizes it through three primitives of decision making: preferences, beliefs, and constraints. First ask what the other person wants, what they think is true, and what limits their available choices. Then predict how each move you could make would change their response. Work backward from those likely responses to your best action. The framework applies to competitors reacting to a price change, a child disengaging from schoolwork, or a rider whose social norm rules out tipping. Its value comes from avoiding expenditure on actions that cannot overcome a binding constraint and from updating your strategy when observed behavior contradicts the model.

Origin

List presents the primitives as a practical way to develop theory of mind within his critical-thinking hierarchy.

Core principles

  • 01Another person's choices follow their preferences, beliefs, and constraints
  • 02Your best move depends partly on how the other person will respond
  • 03A strong constraint can make persuasion spending wasteful
  • 04Backward induction turns a behavioral model into an action

How to run it

  1. 1

    Choose the actor

    Identify whose response affects your result. Define the decision from that person's point of view rather than your own.

    Pro tip Focus on one consequential actor before modeling a crowd.

    Watch out Do not substitute a stereotype for an individual model.

  2. 2

    Map preferences

    Estimate which outcomes the person values and how they rank the tradeoffs. Use behavior and direct evidence where available.

    Pro tip Distinguish what they want from what you want them to want.

    Watch out Stated preferences may not predict actual choices.

  3. 3

    Map beliefs

    Identify what the person believes about the options, probabilities, and other actors. Their action follows their perceived world, even when a belief is inaccurate.

    Pro tip Ask what information they possess that you do not.

    Watch out Do not assume shared facts imply shared interpretation.

  4. 4

    Map constraints

    Find the financial, cognitive, social, legal, or practical limits that remove choices from the person's feasible set. Mark any constraint that your intervention cannot change.

    Pro tip Look for a binding norm or resource limit before spending on persuasion.

    Watch out Ignoring a hard constraint leads to wasted effort.

  5. 5

    Backward induct

    Predict the person's response to each action you could take, then choose the action with the best resulting outcome. Revise the primitives when reality differs from the prediction.

    Pro tip Write the expected response beside each option.

    Watch out A model is a hypothesis, not access to another person's mind.

In the wild

Do not chase the never-tipper

List describes a person who follows a social norm of never tipping. If that norm is a binding constraint, changing prompts or spending more money to induce a tip is unlikely to work. Modeling the constraint first prevents waste.

Resources can be directed toward people whose behavior is actually responsive.

Common mistakes

Projecting your own preferences

Assuming another actor values the same outcomes produces the wrong predicted response.

Ignoring binding constraints

No amount of optimization around a message will work if the recipient cannot or will not choose the target behavior.

Treating the model as certainty

Preferences, beliefs, and constraints are estimates that must change when observed actions contradict them.

Is it for you?

Best for

Negotiations, competitive moves, management decisions, and influence attempts where another person's reaction determines the outcome.

Not ideal for

Decisions that do not materially depend on another actor or where evidence about that actor is too weak to support a useful model.

From the transcript

theory of mind means how well do you put yourself in the shoes of another person

John List · 52:00

try to figure out what are the preferences of that other person what are the beliefs of the other person and what are the constraints…

John List · 56:30

after you figure that out you then say well what's my optimal action given that the person operates in this way

John List · 57:30

From the episode

#566: John List — A Master Economist on Strategic Quitting, How to Practice Theory of Mind, Learnings from Uber, Optimizations to Boost Donations, the Primitives of Decision-Making, and How Field Experiments Reveal Hidden Realities

John List